The present invention relates generally to engines for automotive vehicles, and more particularly, to engines having balance shafts that function as a portion of an alternator.
Alternators are typically mounted on the exterior of an engine and are belt-driven with an accessory belt used to drive various ancillary under hood components that are mounted to the engine. The alternator and the ancillary components occupy much sought after space in the engine compartment. In some cases, it is nearly impossible to provide certain engines for certain vehicles because of the space occupied by the ancillary components. It would therefore be desirable to reduce package space of an engine and the ancillary items.
Engines, particularly 60 degree xe2x80x9cVxe2x80x9d angle V-6 engines, use balance shafts to achieve optimal smoothness during engine operation. Typical balance shafts are located within the crankcase of the engine. The balance shaft counteracts imbalance generated by the reciprocating motion of the masses within the cylinder bores of the engine. When the engine acts in an imbalanced manner, the roughness of the engine may be observed by the operator of the vehicle. It is therefore desirable to provide balance shafts for engines to counteract imbalance.
It is therefore one object of the invention to provide a balance shaft and alternator assembly to reduce package space occupied by the engine. Advantageously, it has been found that by moving the balance shaft from the crankcase environment, the balance shaft may be used to mount a rotor for an alternator within a housing on the exterior of the engine block which may house an alternator stator adjacent to the rotor.
It is therefore one object of the invention to provide an engine having an engine block having an interior portion and an exterior portion; a balance shaft alternator assembly is coupled to the exterior portion of the engine block. The assembly has a housing and a balance shaft rotatably coupled within the housing. The balance shaft is also rotatably coupled to the crankshaft. The housing has a stator fixedly coupled therein. The balance shaft has a rotor that is fixedly coupled thereto. The assembly has a stator adjacent to the rotor that generates electricity upon the rotation of the rotor.
In a further aspect of the invention, a method for generating electrical power and balancing the operator of an engine having an imbalance comprises the steps of:
synchronously coupling a balance shaft to a crankshaft, said balance shaft having a rotor directly coupled thereto;
generating a magnetic field from said rotor;
rotating said rotor adjacent to a stator;
inducing electrical current flow in the stator from the rotor; and,
rotating said balance shaft assembly to counterbalance the imbalance of the engine.
Other objects and features of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and appended claims.